In recent years, active discussions have been conducted about SON (Self Organizing Network), which autonomously optimizes a radio parameter and/or network configuration in a radio communication system such as a cellular system, in the light of operation cost (OPEX) reduction. The standardization of SON functions is also under way in 3GPP LTE (Long Term Evolution) (NPL 1).
SON has functions such as the following:
Self-Configuration;
Self-Optimization; and
Self-Healing.
These are technologies for achieving respective different purposes. Of these functions, the self-healing function is a function such that a radio base station or a network operation management apparatus autonomously performs fault management, and an object thereof is, for example, to detect a problem such as a fault with a network apparatus and autonomously heal the fault (NPL 2).
Hereinafter, the self-healing function will be described briefly by taking a 3GPP LTE radio communication system as an example. Note that a radio base station (enhanced Node B) will be abbreviated to eNB.
Referring to FIG. 1, it is assumed that eNBs 1 and 2 manage cells 1 and 2, respectively, and that a network operation management apparatus (Operation and Management (OAM); hereinafter referred to as an O&M) manages these eNBs 1 and 2. In the case where an O&M has a SON function, it is also referred to as a SON server. Note that for the details of problem detection and self recovery in the self-healing function, the method according to NPL 2 is assumed to be used, and detailed descriptions thereof will be omitted.
As shown in FIG. 1, it is assumed that for network performance monitoring, the eNBs 1 and 2 periodically report a result of measuring service quality or information regarding service quality related to network performance, as network measurement information, to the O&M (Measurement reporting for Performance Monitoring (PM)). Based on this report, the O&M (SON server) monitors whether or not there is a problem with network apparatuses such as the eNBs 1 and 2. It is assumed that a fault occurs in the eNB 1, for example, with a radio transceiver section (Radio Frequency (RF)) at a certain point of time (Occurrence of fault). In this case, the eNB 1 reports the then measurement information to the O&M. Based on this measurement information, the O&M detects that some problem has occurred at the eNB 1 (Problem detection). For example, the O&M detects a failure by recognizing that the value of service quality indicated by this measurement information has suddenly degraded (the details thereof will be omitted). The O&M issues to the eNB 1 an instruction for self recovery such as, for example, reboot (Indication of self recovery activation). In accordance with this instruction, the eNB 1 executes self recovery such as reboot (Self recovery). Then, when completing the self recovery, the eNB 1 sends a completion notification to the O&M (Indication of self recovery completion).
In this manner, when a problem occurs at an eNB or a network apparatus, the O&M (SON server) detects the problem and issues an instruction for self recovery to the target eNB or network apparatus. In accordance with this instruction for self recovery, this eNB or network apparatus executes self recovery, whereby self-healing in a radio network system can be accomplished. Note that it is also conceivable that the above-described self-healing function is, in some cases, provided to a radio base station or network apparatus itself, instead to being provided to a network operation management apparatus.